The subject of the present invention is a foot securing device, particularly for ski boots.
It is known that with particular footwear, such as ski boots, it is necessary, both for the athlete's safety and to be able to control the skis which are attached to the boots themselves, that the foot be well secured against movement or internal looseness.
On the other hand, for comfort, it is necessary that the boot compresses the foot as evenly as possible, without areas of excessive compression and areas of looseness on the foot itself.
Areas of excessive compression cause, in fact, pain or discomfort, whilst those areas where the foot is loose do not cooperate in transferring the stresses to the implements, giving the athlete instead a feel of unsafety and instability.
To solve this problem, many devices have been developed which, in general, may be classed as external devices and internal devices.
To the first class belong all the various adjustable levers which, being associated with the boot shell additionally to closing it make it possible to locally pull the shell flaps with a greater or lesser force such that this effect is also reflected on the inner shoe and hence also on the foot.
That adjustment is not very effective because it is of substantially indirect type in that the foot compression can only take place by deformation of the boot shell.
Among the internal devices, known are ties or small cables which act substantially on the foot instep of the inner shoe and which are connected through force adjustment means to a pair of fixed points rigid with the inner portion of the boot shell.
Also in this case there are many drawbacks, particularly due to the fact that the foot compression takes place at particularly restricted areas with an uneven securing effect.
Other devices provide for lifting or lowering an inner wedge heel, consequently decreasing the shell's inside volume, but also in this case foot securing is still achieved by tightening a set of external linkages.
In this case the device is inconvenient to adjust in addition to not being particularly effective.
It should be also noted that there is considerable difficulty in devising a perfect tightening device, because the feet of each person have a different anatomical configuration.